Worked example 1
Decode with shift 3 backwards: KHOOR
- K→H, H→E, O→L, O→L, R→O.
Answer: HELLO
Brain Training · Mixed
Cryptograms: crack the code puzzles
A cryptogram is a message where letters have been swapped by a rule. Cracking it trains pattern spotting and persistence.
- 1Learn it
- 2See it worked
- 3Try it online
- 4Print it
- 5Check your answer
Before you start
Who it's for and what to know first
Knowing the alphabet in order.
Learn it
How it works
- Caesar shift: every letter moves the same number of places. Shift 1: A→B, B→C, … Z→A.
- To decode, shift backwards by the same amount.
- For unknown substitutions, look for one-letter words (usually A or I) and common three-letter words (THE, AND).
- E, T and A are the most common letters in English.
Try it online · print it · check it
Practice questions
Tips
Common mistakes
- Shifting forwards instead of backwards.
- Forgetting to wrap round from A back to Z.
Last reviewed: 25 September 2026